Annie Machon and David Shayler, who worked in MI5’s counter-subversion and Irish-terrorism branches, resigned in October 1996 and alleged that the agency illegally tapped phones, maintained files on political figures, misled government oversight officials, and possessed advance intelligence about bombings. Shayler gave classified material to The Mail on Sunday; its first report, published on 24 August 1997, alleged extensive surveillance of people labeled subversives, including claims that then-politician Peter Mandelson’s telephone had been monitored for three years. Courts imposed an injunction restricting publication of some allegations, and the claims about prior knowledge of attacks and an alleged plot to assassinate Muammar Gaddafi remained contested rather than established findings.
Machon and Shayler fled across Europe after resigning. France declined to extradite Shayler after his 1998 arrest, treating the case as political, but he returned to Britain with Machon in August 2000 and was imprisoned for six months in November 2002 for offenses under the Official Secrets Act. Machon was never charged. The episode exposed the legal vulnerability of intelligence whistleblowers and kept questions about MI5 oversight, secrecy, and surveillance in public debate; Machon later addressed electronic mass surveillance before the European Parliament’s civil-liberties committee in 2013.
